io.prestosql.connector.system.SystemSplitManager.java Source code

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Here is the source code for io.prestosql.connector.system.SystemSplitManager.java

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/*
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
package io.prestosql.connector.system;

import com.google.common.collect.ImmutableList;
import com.google.common.collect.ImmutableSet;
import io.prestosql.metadata.InternalNodeManager;
import io.prestosql.spi.HostAddress;
import io.prestosql.spi.Node;
import io.prestosql.spi.PrestoException;
import io.prestosql.spi.connector.ColumnHandle;
import io.prestosql.spi.connector.ConnectorSession;
import io.prestosql.spi.connector.ConnectorSplit;
import io.prestosql.spi.connector.ConnectorSplitManager;
import io.prestosql.spi.connector.ConnectorSplitSource;
import io.prestosql.spi.connector.ConnectorTableLayoutHandle;
import io.prestosql.spi.connector.ConnectorTransactionHandle;
import io.prestosql.spi.connector.FixedSplitSource;
import io.prestosql.spi.connector.SystemTable;
import io.prestosql.spi.connector.SystemTable.Distribution;
import io.prestosql.spi.predicate.TupleDomain;

import java.util.Set;

import static io.prestosql.spi.NodeState.ACTIVE;
import static io.prestosql.spi.StandardErrorCode.NOT_FOUND;
import static io.prestosql.spi.connector.SystemTable.Distribution.ALL_COORDINATORS;
import static io.prestosql.spi.connector.SystemTable.Distribution.ALL_NODES;
import static io.prestosql.spi.connector.SystemTable.Distribution.SINGLE_COORDINATOR;
import static java.lang.String.format;
import static java.util.Objects.requireNonNull;

public class SystemSplitManager implements ConnectorSplitManager {
    private final InternalNodeManager nodeManager;
    private final SystemTablesProvider tables;

    public SystemSplitManager(InternalNodeManager nodeManager, SystemTablesProvider tables) {
        this.nodeManager = requireNonNull(nodeManager, "nodeManager is null");
        this.tables = requireNonNull(tables, "tables is null");
    }

    @Override
    public ConnectorSplitSource getSplits(ConnectorTransactionHandle transactionHandle, ConnectorSession session,
            ConnectorTableLayoutHandle layout, SplitSchedulingStrategy splitSchedulingStrategy) {
        SystemTableLayoutHandle layoutHandle = (SystemTableLayoutHandle) layout;
        SystemTableHandle tableHandle = layoutHandle.getTable();

        TupleDomain<ColumnHandle> constraint = layoutHandle.getConstraint();
        SystemTable systemTable = tables.getSystemTable(session, tableHandle.getSchemaTableName())
                // table might disappear in the meantime
                .orElseThrow(() -> new PrestoException(NOT_FOUND,
                        format("Table %s not found", tableHandle.getSchemaTableName())));

        Distribution tableDistributionMode = systemTable.getDistribution();
        if (tableDistributionMode == SINGLE_COORDINATOR) {
            HostAddress address = nodeManager.getCurrentNode().getHostAndPort();
            ConnectorSplit split = new SystemSplit(tableHandle.getConnectorId(), tableHandle, address, constraint);
            return new FixedSplitSource(ImmutableList.of(split));
        }

        ImmutableList.Builder<ConnectorSplit> splits = ImmutableList.builder();
        ImmutableSet.Builder<Node> nodes = ImmutableSet.builder();
        if (tableDistributionMode == ALL_COORDINATORS) {
            nodes.addAll(nodeManager.getCoordinators());
        } else if (tableDistributionMode == ALL_NODES) {
            nodes.addAll(nodeManager.getNodes(ACTIVE));
        }
        Set<Node> nodeSet = nodes.build();
        for (Node node : nodeSet) {
            splits.add(
                    new SystemSplit(tableHandle.getConnectorId(), tableHandle, node.getHostAndPort(), constraint));
        }
        return new FixedSplitSource(splits.build());
    }
}